1. Field of Invention
This invention relates to devices and methods for the filtration of air. More particularly, this invention relates to air purifiers capable of providing a level of air quality suitable for environments that are highly sensitive to airborne contaminants, e.g., in vitro fertilization laboratories or other medical environments. Further, the invention may be adapted for use in any substantially enclosed environment, including, but not limited to, homes, residential buildings, commercial buildings, hotels, cars, buses, trains, airplanes, cruise ships, educational facilities, offices, and government buildings. The invention may also have applications in, e.g., national security, defense, or airline industries.
2. Description of Related Art
In vitro fertilization (“IVF”) is a procedure whereby egg cells are fertilized by sperm in a laboratory environment, instead of in the womb. If an egg cell is successfully fertilized, it may be transferred into the uterus of a patient wishing to become pregnant. IVF may be an effective option for patients suffering from infertility, especially where other methods of assisted reproduction have failed. However, IVF is very expensive and is not typically covered by medical insurance. In 2009, the cost of a single cycle of IVF was approximately $10,000 to $15,000 in the United States. It is financially prohibitive for most people to undergo multiple rounds of IVF. It is therefore imperative that conditions for successful pre-implantation embryogenesis are optimized, in order to maximize the likelihood of success.
One extremely important factor contributing to the likelihood of successful pre-implantation embryogenesis is the air quality of the IVF laboratory. Gametes and embryos grown in vitro are highly sensitive to environmental influences. Human embryos have no means of protection or filtration against environmental toxins and pathogens. They are completely at the mercy of their environment. The incubators which house the human embryos often consist of a significant percentage of room air. Although airborne contaminants can adversely affect embryogenesis, surprisingly little emphasis has been placed on optimizing laboratory air quality during the last three decades in which IVF has been available as a treatment for infertility.
Existing filtration devices have been found insufficient to optimize air quality to truly acceptable levels for IVF. For example, it has been found that laboratory air that had been filtered with only high efficiency particulate air (“HEPA”) filters was actually of lesser quality than outside air. Additionally, some filters produce by-products or other contaminants that actually detract from the quality of the air in an IVF laboratory. For example, carbon filters can create carbon dusting that is harmful to the NF process. This is not to say, however, that carbon filters or HEPA filters should not be used to treat air supplied to an IVF laboratory. On the contrary, it is preferred that carbon filters, HEPA filters, or their respective equivalents, are included among filtration media used to treat air supplied to an IVF laboratory. Attaining optimal air quality in an IVF laboratory or other substantially enclosed space requires proper selection, combination and sequencing of various filtration media.